Flexible and steerable elongate instruments with shape control and support elements

ABSTRACT

An instrument having a flexible and elongated body includes at least a lumen and a flex member disposed within the lumen. The flex member may be capable of providing steering control to a first portion of the elongate body while providing load bearing support to a second portion of the elongate body. A pull wire may be disposed within the flex member, and at least a distal portion of the pull wire may be coupled to the elongate body and a proximal portion of the pull wire may be operatively coupled to a control unit. The control unit may be coupled to a proximal portion of the elongate body. In addition, a control member may be operatively coupled to the control unit such that a distal portion of the control member may be positioned near a proximal portion of the flex member. The control member may be configured to support the flex member and control the movement or displacement of the flex member. Furthermore, the flex member may be configured to selectively decouple articulation or steering forces of a first portion of the elongate body away from a second portion of the elongate body; thereby, preventing compression of the second portion of the elongate body while maintaining elasticity or flexibility of the second portion of the elongate body.

FIELD OF INVENTION

The present invention relates generally to robotically controlled systems, such as robotic or telerobotic surgical systems, and more particularly to flexible and steerable elongate instruments or catheters with adjustable or changeable shape and articulation control for performing minimally invasive surgical operations.

BACKGROUND

Standard surgical procedures or open surgeries typically involve using a scalpel to create an opening of sufficient size to allow a surgical team to gain access to an area in the body of a patient for the surgical team to diagnose and treat one or more target sites. When possible, minimally invasive surgical procedures may be used instead of standard surgical procedures to minimize physical trauma to the patient and reduce recovery time for the patient to recuperate from the surgical procedures. However, minimally invasive surgical procedures typically require using extension tools to approach and address the target site, and the typical extension tools may be difficult to use, manipulate, and control. Consequently, only a limited number of surgeons may have the necessary skills to proficiently manipulate and control the extension tools for performing complex minimally invasive surgical procedures. As such, standard surgical procedures or open surgery might be chosen for the patient even though minimally invasive surgical procedures may be more effective and beneficial for treating the patient.

Accordingly, there is a need to develop extension tools that are easy to use, manipulate, and control, especially for performing complex minimally invasive surgical procedures.

SUMMARY

In accordance with one embodiment, a steerable elongate instrument has an elongate body with a first lumen and a second lumen within the elongate body. A flex member may be disposed within the second lumen, and a pull wire may be disposed within the flex member. A distal portion of the pull wire may be coupled to a distal portion of the elongate body and a proximal portion of the pull wire may be operatively coupled to a control unit. The control unit may be coupled to a proximal portion of the elongate body.

According to another embodiment, a steerable elongate instrument has an elongate body with a primary lumen, a plurality of secondary lumens within the elongate body, and a plurality of flex members wherein each one of the flex members may be disposed within each one of the plurality of secondary lumens. The steerable elongate instrument may further include a plurality of pull wires wherein each of the pull wires may be respectively disposed within one of the flex members, and the distal portions of the pull wires may be coupled to different locations or portions of the elongate body and proximal portions of the pull wires may be operatively coupled to a control unit. The control unit may be coupled to a proximal portion of the elongate body.

According to another embodiment, a steerable elongated instrument has an elongate body with a plurality of lumens within the elongate body. The steerable elongate instrument may also include a plurality of flex members, and each of the flex members may be respectively disposed within each one of the lumens. The steerable elongate instrument may further include a plurality of pull wires, and each of the pull wires may be respectively disposed within one of the flex members such that distal portions of the pull wires may be coupled to different locations or portions of the elongate body and proximal portions of the pull wires may be operatively coupled to a control unit. The control unit may be coupled to a proximal portion of the elongate body.

According to another embodiment, a steerable elongate instrument has an elongate body with a first lumen and a second lumen within the elongate body. A flex member may be disposed within the second lumen, and the flex member may be configured to provide steering control to a first portion of the elongate body and load bearing support to a second portion of the elongate body. A pull wire may be disposed within the flex member wherein a distal portion of the pull wire may be coupled to a distal portion of the elongate and a proximal portion of the pull wire may be operatively coupled to a control unit. The control unit may be coupled to a proximal portion of the elongate body and the control unit may be configured to operate the pull wire for applying forces to articulate or steer the first portion of the elongate body.

According to another embodiment, a steerable elongate instrument has an elongate body with a primary lumen and a plurality of secondary lumens within the elongate body. The elongate instrument may also include a plurality of flex members such that each of the flex members may be respectively disposed within each of the plurality of secondary lumens. The flex members may be configured to provide steering control to different distal portions of the elongate body and load bearing support to different proximal portions of the elongate body. The elongate instrument further includes a plurality of pull wires and each of the pull wires may be respectively disposed within each of the plurality of the flex members. The distal portions of the pull wires may be coupled to different distal locations or portions of the elongate body and proximal portions of the pull wires may be operatively coupled to a control unit. The control unit may be coupled to a proximal portion of the elongate body, and the control unit may be configured to operate the pull wires for applying forces to articulate or steer the different distal locations or portions of the elongate body.

According to another embodiment, a steerable elongate instrument has an elongate body with a plurality of lumens within the elongate body. The elongate instrument also has a plurality of flex members, and each of the flex members may be respectively disposed within each of the plurality of lumens. The flex members may be configured to provide steering control to different distal portions of the elongate body and load bearing support to different proximal portions of the elongate body. The elongate instrument also includes a plurality of pull wires, and each of the pull wires may be respectively disposed within each of the flex members. Distal portion of respective pull wires may be coupled to different distal locations or portions of the elongate body, and proximal portion of respective pull wires may be operatively coupled to a control unit. The control unit may be coupled to a proximal portion of the elongate body. The control unit may be configured to operate the respective pull wires for applying forces or loads to articulate or steer the different distal locations or portions of the elongate body.

According to another embodiment, an instrument has a flexible and elongate body that has at least one lumen. A flex member may be disposed within the lumen, and the flex member may be capable of providing steering control to a first portion of the elongate body while providing load bearing support to a second portion of the elongate body. A pull wire may be disposed within the flex member, and at least a distal portion of the pull wire may coupled to the elongate body and a proximal portion of the pull wire may be operatively coupled to a control unit. The control unit may be coupled to a proximal portion of the elongate body.

According to another embodiment, an instrument includes a flexible and elongate body that has at least one lumen. A flex member may be disposed within the lumen, and the flex member may be capable of providing steering control to a first portion of the elongate body while providing load bearing support to a second portion of the elongate body. A pull wire may be disposed within the flex member, and at least a distal portion of the pull wire may coupled to the elongate body and a proximal portion of the pull wire may be operatively coupled to a control unit. The control unit may be coupled to a proximal portion of the elongate body. The flex member may be further configured to selectively decouple articulation or steering forces of a first portion of the elongate body away from a second portion of the elongate body; thereby, preventing compression of the second portion of the elongate body while maintaining elasticity or flexibility of the second portion of the elongate body.

According to another embodiment, a method of shape or articulation control of an elongate instrument may be provided. The method may include inserting an elongate instrument into a patient through either an incision or orifice, advancing the elongate instrument through a pathway inside the patient, manipulating the elongate instrument to conform or match a shape or curvature of the pathway as the elongate instrument is being advanced through the pathway, and steering or articulating a distal portion of the elongate instrument around other curvatures of the pathway.

According to another embodiment, a steerable elongate instrument has an elongate body with a first lumen and a second lumen within the elongate body, and a flex member may be disposed within the second lumen. A pull wire may be disposed within the flex member, wherein a distal portion of the pull wire may be coupled to a distal portion of the elongate body and a proximal portion of the pull wire may be operatively coupled to a control unit. The control unit may be coupled to a proximal portion of the elongate body, and a control member may be operatively coupled to the control unit wherein a distal portion of the control member may be positioned near a proximal portion of the flex member.

According to another embodiment, a steerable elongate instrument has an elongate body with a primary lumen and a plurality of secondary lumens within the elongate body. The steerable elongate instrument may also include a plurality of flex members, and each of the plurality of flex members may be respectively disposed within each of the secondary lumens. The steerable elongate instrument may further include a plurality of pull wires wherein each of the pull wires may be respectively disposed within each of the flex members, and distal portion of each of the pull wires may be coupled to different locations or portions of the elongate body and proximal portion of each of the pull wires are operatively coupled to a control unit. The control unit may be coupled to a proximal portion of the elongate body. A plurality of control members may be operatively coupled to the control unit such that distal portions of the control members may positioned near the proximal portions of the flex members.

According to another embodiment, a steerable elongate instrument has an elongate body with a plurality of lumens within the elongate body and a plurality of flex members. Each of the flex members may be respectively disposed within each of the lumens. The steerable elongate instrument may also includes a plurality of pull wires, and each of the pull wires may be respectively disposed within each of the flex members such that distal portion of each of the pull wires may coupled to different locations or portions of the elongate body and proximal portion of each of the pull wires may be operatively coupled to a control unit. The control unit may be coupled to a proximal portion of the elongate body, and a plurality of control members may be operatively coupled to the control unit wherein distal portions of the control members may be positioned near the proximal portions of the flex members.

According to another embodiment, a steerable elongate instrument has an elongate body having a first lumen and a second lumen within the elongate body and a flex member disposed within the second lumen. The flex member may be configured to provide steering control to a first portion of the elongate body and load bearing support to a second portion of the elongate body. A pull wire may be disposed within the flex member, and a distal portion of the pull wire may be coupled to a distal location or portion of the elongate body and a proximal portion of the pull wire may be operatively coupled to a control unit. The control unit may be coupled to a proximal portion of the elongate body and the control unit may be configured to operate the pull wire for applying forces to articulate or steer the first portion of the elongate body. A control member may be operatively coupled to the control unit wherein a distal portion of the control member may be positioned near a proximal portion of the flex member. The control member may be configured to support the flex member and control movement or displacement of the flex member.

According to another embodiment, an instrument having a flexible and elongated body includes at least a lumen and a flex member disposed within the lumen. The flex member may be configured to provide steering control to a first portion of the elongate body while providing load bearing support to a second portion of the elongate body. A pull wire may be disposed within the flex member, and at least a distal portion of the pull wire may be coupled to the elongate body and a proximal portion of the pull wire may be operatively coupled to a control unit. The control unit may be coupled to a proximal portion of the elongate body. In addition, a control member may be operatively coupled to the control unit such that a distal portion of the control member may be positioned near a proximal portion of the flex member. The control member may be configured to support the flex member and control the movement or displacement of the flex member. Furthermore, the flex member may be configured to selectively decouple articulation or steering forces of a first portion of the elongate body away from a second portion of the elongate body; thereby, preventing compression of the second portion of the elongate body while maintaining elasticity or flexibility of the second portion of the elongate body.

According to another embodiment, a steerable elongate instrument has an elongate body with a primary lumen, a plurality of secondary lumens within the elongate body, and a plurality of flex members. Each of the plurality of flex members may be disposed within each of the secondary lumens. The flex members may be configured to provide steering control to different distal portions of the elongate body and load bearing support to different proximal portions of the elongate body. The steerable elongate instrument may also include a plurality of pull wires wherein each of the pull wires may be disposed within each of the flex members. In addition, distal portion of each of the pull wires may be coupled to different distal locations or portions of the elongate body and proximal portion of each of the pull wires may be operatively coupled to a control unit. The control unit may be coupled may be coupled to a proximal portion of the elongate body. Furthermore, a plurality of control members may be operatively coupled to the control unit wherein distal portions of the control members may be positioned near the proximal portions of the flex members, and the control members may be configured to support the flex members and control movement or displacement of the flex members.

According to another embodiment, a steerable elongate instrument has an elongate body with a plurality of lumens within the elongate body and a plurality of flex members. Each of the flex members may be disposed within each of the lumens, and the flex members may be configured to provide steering control to different distal portions of the elongate body and load bearing support to different proximal portions of the elongate body. The steerable elongate instrument may also include a plurality of pull wires. Each of the pull wires may be disposed within each of the flex members, wherein distal portion of each of the pull wires may be coupled to different distal locations or portions of the elongate body and proximal portion of each of the pull wires may be operatively coupled to a control unit. The control unit may be coupled to a proximal portion of the elongate body. The steerable instrument may further include a plurality of control members that may be operatively coupled to the control unit such that distal portions of the control members may be positioned near the proximal portions of the flex members. The control members may be configured to support the flex members and control movement or displacement of the flex members.

According to another embodiment, a method of shape or articulation control of an elongate instrument may be provided. The method may include inserting an elongate instrument into a patient through either an incision or orifice, advancing the elongate instrument through a pathway inside the patient, manipulating the elongate instrument to conform or match a shape or curvature of the pathway as the elongate instrument is being advanced through the pathway, and steering or articulating a distal portion of the elongate instrument around other curvatures of the pathway. In addition, the method may further include advancing a control member against a proximal portion of a flex member of the elongate instrument. The method may also include locking the conformed or matched shape or curvature of a proximal portion of the elongate instrument.

According to another embodiment, a method of shape of articulation control of an instrument may be provided. The method may include inserting an elongate instrument into a patient, wherein the elongate instrument comprises a distal portion, a mid portion, and a proximal portion. The method may also include advancing the distal and mid portions of the elongate instrument through a pathway inside the patient, manipulating the mid portion of the elongate instrument to conform to a shape or curvatures in the pathway as the elongate instrument is being advanced through the pathway, and locking the mid portion of the elongate instrument such that the mid portion maintains the conformed shape or curvatures while the distal portion of the elongate instrument is manipulated to assume a curvature independent of the mid portion.

According to another embodiment, a steerable elongate instrument has an elongate body with a first lumen and a second lumen within the elongate body, a flex member disposed within the second lumen, and a first pull wire disposed within the flex member wherein a distal portion of the first pull wire may be coupled to a distal portion of the elongate body and a proximal portion of the first pull wire may be operatively coupled to a control unit. The control unit may be coupled to a proximal portion of the elongate body. A second pull wire may be disposed within the flex member, and a distal portion of the second pull wire may be coupled to a distal portion of the flex member and a proximal portion of the second pull wire may be operatively coupled to the control unit. Additionally, a control member may be operatively coupled to control unit such that a distal portion of the control member may be positioned near a proximal portion of the flex member.

According to another embodiment, a steerable elongate instrument has an elongate body with a first lumen and a second lumen within the elongate body, and a flex member disposed within the second lumen. The flex member may be configured to provide steering control to a first portion of the elongate body and load bearing support to a second portion of the elongate body. The steerable instrument may also include a first pull wire and a second pull wire. A distal portion of the first pull wire may be coupled to a distal portion of the elongate body and a proximal portion of the first pull wire may be operatively coupled to a control unit. The control unit may be coupled to a proximal portion of the elongate body, and the control unit may be configured to operate the first pull wire for applying forces to articulate or steer the first portion of the elongate body. In addition, a distal portion of the second pull wire may be coupled to a distal portion of the flex member and a proximal portion of the second pull wire may be operatively coupled to the control unit. The control unit may be configured to operate the second pull wire to control displacement of the flex member. The steerable instrument may further include a control member that may be operatively coupled to the control unit such that a distal portion of the control member may be positioned near a proximal portion of the flex member.

The control member may be configured to control displacement of the flex member. According to another embodiment, a method for shape or articulation control may be provided. The method may include inserting an elongate instrument into a patient through either an incision or orifice, advancing the elongate instrument through a pathway inside the patient, manipulating the elongate instrument to conform or match a shape or curvature of the pathway as the elongate instrument is being advanced through the pathway, controlling the displacement of a flex member along a length of the elongate instrument, and steering a first portion or a second portion of the elongate instrument around curvatures of the pathway.

According to another embodiment, a method of shape or articulation control may be provided. The method may include inserting an elongate instrument into a patient through either an incision or orifice, advancing the elongate instrument through a pathway inside the patient, manipulating the elongate instrument to conform or match a shape or curvature of the pathway as the elongate instrument is being advanced through the pathway, controlling the displacement of a flex member along a length of the elongate instrument, altering the stiffness of a first portion of the elongate instrument, changing the radius of curvature of the elongate instrument, and steering the first portion or second portion of the elongate instrument around curvatures of the pathway.

According to another embodiment, an instrument having a flexible and elongated body includes at least two lumens and a flex member disposed within one of the lumens. The flex member may be capable of providing steering control to a first portion of the elongate body while providing load bearing support to a second portion of the elongate body. A pull wire may be disposed within the flex member, and at least a distal portion of the pull wire may be coupled to the elongate body and a proximal portion of the pull wire may be operatively coupled to a control unit. The control unit may be coupled to a proximal portion of the elongate body. In addition, a control member may be operatively coupled to the control unit such that a distal portion of the control member may be positioned near a proximal portion of the flex member. The control member may be configured to support the flex member and control the movement or displacement of the flex member. Furthermore, the flex member may be configured to be anchored to the elongate body between the first and second portion of the elongate body to selectively decouple articulation or steering forces of a first portion of the elongate body away from a second portion of the elongate body; thereby, preventing twist or compression of the second portion of the elongate body while maintaining elasticity or flexibility of the second portion of the elongate body.

According to another embodiment, an instrument having a flexible and elongated body includes at least two lumens and a flex member disposed within one of the lumens. The flex member may be capable of providing steering control to a first portion of the elongate body while providing load bearing support to a second portion of the elongate body. A pull wire may be disposed within the flex member, and at least a distal portion of the pull wire may be coupled to the elongate body and a proximal portion of the pull wire may be operatively coupled to a control unit. The control unit may be coupled to a proximal portion of the elongate body. In addition, a control member may be operatively coupled to the control unit such that a distal portion of the control member may be positioned near a proximal portion of the flex member. The control member may be configured to support the flex member and control the movement or displacement of the flex member. Furthermore, the flex member may be configured to be anchored to the elongate body between the first and second portion of the elongate body to selectively decouple articulation or steering forces of a first portion of the elongate body away from a second portion of the elongate body; thereby, preventing twist or compression of the second portion of the elongate body while maintaining elasticity or flexibility of the second portion of the elongate body. In addition, the flex member may not be anchored to the elongate body; instead, it may be positioned at various locations of the elongate body to affect or alter the bending stiffness of various sections or portions of the elongate body. Moreover, by way of a retractable anchor, the flex tube may operate as a structure or device that decouples articulation forces from at least a portion of the elongate body, and the flex tube may also operate as a structure or device that could affect or alter the bending stiffness to at least a portion of the elongate body.

Other and further features and advantages of embodiments of the invention will become apparent from the following detailed description, when read in view of the accompanying figures.

BRIEF DESCRIPTION OF THE DRAWINGS

The present invention will be readily understood by the following detailed description, taken in conjunction with accompanying drawings, illustrating by way of examples the principles of the invention. The objects and elements in the drawings are not necessarily drawn to scale, proportion, precise orientation or positional relationships; instead, emphasis is focused on illustrating the principles of the invention. The drawings illustrate the design and utility of various embodiments of the present invention, in which like elements are referred to by like reference symbols or numerals. The drawings, however, depict the embodiments of the invention, and should not be taken as limiting its scope. With this understanding, the embodiments of the invention will be described and explained with specificity and detail through the use of the accompanying drawings in which:

FIG. 1 illustrates one example of a robotic or telerobotic surgical system.

FIG. 2A through FIG. 2D illustrate various embodiments of an instrument assembly.

FIG. 3A illustrates a cross-sectional view of a flexible and steerable elongate instrument with variable or changeable shape control and support elements in accordance with one embodiment.

FIG. 3B illustrates another cross-sectional view (View 1-1) of a flexible and steerable elongate instrument with variable or changeable shape control and support elements in accordance with one embodiment.

FIG. 4A illustrates an elongate instrument with passively controlled flex member in accordance with one embodiment.

FIG. 4B illustrates a passively controlled flex member with a service or buffer loop in accordance with one embodiment.

FIG. 4C illustrates support tubes or support members sliding along the flex tubes or flex members in accordance with one embodiment.

FIG. 4D illustrates slidable couplings of variable shape control and support components near the proximal section of a flexible and steerable elongate instrument in accordance with one embodiment.

FIG. 5A through FIG. 5D illustrate rack and pinion drive mechanisms in a drive unit or splayer for variable shape control and support in accordance with one embodiment.

FIG. 6A through FIG. 6C illustrate the operation of a substantially flexible and steerable elongate instrument in accordance with one embodiment.

FIG. 7A through FIG. 7C illustrate the operation of a substantially flexible and steerable elongate instrument in accordance with one embodiment.

FIG. 8A and FIG. 8B illustrate curve aligned steering of a flexible and steerable elongate instrument in accordance with one embodiment.

FIG. 9 illustrates the mechanics of variable shape control and support features of a flexible and steerable elongate instrument in which an “S” shaped curve may be formed in accordance with one embodiment.

FIG. 10 illustrates the mechanics of variable shape control and support features of a flexible elongate instrument in which a “J” shaped curve may be formed in accordance with one embodiment.

FIG. 11A illustrates one embodiment of an elongate instrument with movable or displaceable flex tubes in accordance with one embodiment.

FIG. 11B and FIG. 11C illustrate how movable flex tubes may change the properties of an elongate instrument to form various shapes and/or curvatures in accordance with one embodiment.

FIG. 12A through FIG. 12F illustrate a deployable and retractable anchor in accordance with one embodiment.

FIG. 13A through FIG. 13F illustrate a control unit or splayer configured to operate multiple flex tubes or flex members in accordance with one embodiment.

FIG. 14A through 14D illustrate various embodiments of elongate instruments having flex tubes located or secured at various positions or locations along the length of the elongate instruments.

FIG. 15A through 15C illustrate a simplified construction of an elongate instrument (1500) with variable shape control and support in accordance with one embodiment.

FIG. 16A through 16F illustrate a sample of variations in which one set of flex tubes may be configured or implemented in a set of control lumens within the body of an elongate instrument.

FIG. 16G through FIG. 16J illustrate a sample of variations in which a plurality of flex tubes may be disposed or implemented in a control lumen of an elongate instrument.

FIG. 16I and FIG. 16J illustrate a sample of variations in which one of the plurality of flex tubes in a control lumen may be configured in a passively controlled manner, while one or more other flex tubes may be configured in a passively controlled manner, actively controlled manner, or displaceable controlled manner.

FIG. 17A through FIG. 17F illustrate various methods in which an elongate instrument with passive control, active control, or displaceable control may be used to approach and treat a target site or tissue structure in a minimally invasive procedure.

DETAILED DESCRIPTION OF ILLUSTRATED EMBODIMENTS

Reference will now be made in detail to the preferred embodiments of the present invention, examples of which are illustrated in the accompanying drawings. While the invention will be described in conjunction with the preferred embodiments, it will be understood that they are not intended to limit the scope of the invention to these embodiments. On the contrary, the invention is intended to cover alternatives, modifications, and equivalents that may be included within the spirit and scope of the invention. Furthermore, in the following detailed description of the present invention, numerous specific details are set forth in to order to provide a thorough understanding of the present invention. However, it will be readily apparent to one of ordinary skilled in the art that the present invention may be practiced without these specific details.

The contents of the following applications are incorporated herein by reference as though set forth in full for all purposes: U.S. patent application Ser. No. 11/073,363, filed on Mar. 4, 2005; U.S. patent application Ser. No. 11/418,398, filed on May 3, 2006; U.S. patent application Ser. No. 11/637,951, filed on Dec. 11, 2006; and U.S. patent application Ser. No. 12/079,500, filed on Mar. 26, 2008. All of the following technologies may be utilized or compatible with manually or robotically steerable instruments, such as those described in the aforementioned U.S. patent application Ser. No. 11/073,363; U.S. patent application Ser. No. 11/418,398; U.S. patent application Ser. No. 11/637,951; and U.S. patent application Ser. No. 12/079,500. FIG. 1 illustrates one example of a robotic or telerobotic surgical system (100), e.g., the Sensei® Robotic Catheter System from Hansen Medical, Inc. in Mountain View, Calif., U.S.A., with an operator control station (102) located remotely from an operating table (104) to which an electromechanical device, instrument driver, or robotic catheter manipulator (RCM) (106) and instrument assembly or steerable catheter assembly (108), e.g., the Artisan™ Control Catheter also from Hansen Medical, Inc. in Mountain View, Calif., U.S.A., may be supported by an instrument driver mounting brace (110) that is mounted on the operation table (104). A wired connection (112) transfers signals between an electronics rack (114) near the operator control station (102) and the instrument driver (106) mounted near the operation table (104). The electronics rack (114) includes system hardware and software that operate and perform the many functions of the robotic or telerobotic surgical system (100). The instrument driver mounting brace (110) may be a substantially arcuate-shaped structural member configured to position the instrument driver (106) above a patient (not shown) who is lying on the operating table (104). The wired connection (112) may transmit manipulation, articulation, and control commands from an operator or surgeon (116) who is working at the operator control station (102) and who may be providing the necessary input to the instrument driver (106) by way of one or more input devices, such as an instinctive Motion™ controller (118), joystick, keyboard (120), trackball, data gloves, exoskeletal gloves, or the like, for operating the instrument assembly (108) to perform various operations, such as minimally invasive procedures, on the patient who is lying on the operating table (104). The wired connection (112) may also transmit information (e.g., visual, tactile, force feedback, position, orientation, shape, localization, electrocardiogram, etc.) from the instrument assembly (108), patient, and operation site monitors (not shown in this figure) to the operator control station (102) for providing the necessary information to the operator or surgeon (116) to facilitate monitoring the instruments, patient, and target site for performing various precise manipulation and control of the instrument assembly (108) during minimally invasive surgical procedures. The wired connection (112) may be a hard wire connection, such as an electrical wire configured to transmit electrical signals (e.g., digital signals, analog signals, etc.), an optical fiber configured to transmit optical signals, a wireless link connection configured to transmit various types of wireless signals (e.g., RF signals, microwave signals, etc.), etc., or any combinations of electrical wire, optical fiber, and/or wireless links. The wire connection (112) allows the surgeon or operator (116) to be remotely located from the patient. The surgeon or operator (116) may be located across the operation room from the patient, in a different room, in a different building, or in a different geographical region away from where the patient is located. Information or feedback transmitted by way of the wire connection (112) may be displayed on one or more monitors (122) at the operator control station (102).

FIG. 2A through FIG. 2D illustrate various embodiments of an instrument assembly (108) that may be configured to perform various minimally invasive surgical procedures. An instrument assembly (108) may be comprised of a single steerable elongate instrument assembly or catheter system, as illustrated in FIG. 2A, or a combination of steerable elongate instrument assemblies or catheter systems, as illustrated in FIG. 2B through 2D. As illustrated in FIG. 2B through 2D, the steerable elongate instrument assemblies or catheter systems may be positioned or mounted in a substantially coaxial manner and configured to be operated in a substantially coordinated or tandem-type manner or as a coordinated or tandem-type combination. As described in the aforementioned patent applications that have been incorporated by reference, the instrument assembly (108) may include a control unit or splayer; which may be comprised of gears, pulleys, and control or pull wires to steer or articulate an elongate instrument or catheter in various degrees of motion (e.g., up, down, pitch, yaw, or any motion in-between as well as any other motions). For example, FIG. 2A illustrates one embodiment of an instrument assembly or catheter system (108) which includes a control unit (202) that may be configured to steer an elongate instrument or catheter (204). FIG. 2B illustrates another embodiment of an instrument assembly (108) that includes a combination of steerable elongate instrument assemblies or catheter systems which includes respective control units (202 and 212) and corresponding associated elongate instruments or catheters (204 and 214). The elongate instrument assemblies or catheter systems, as those illustrated in FIG. 2B as well as other similar systems or combinations, may be positioned or mounted coaxially with the elongate instrument or catheter of one elongate instrument assembly or catheter system threaded or loaded through a lumen of another elongate instrument assembly or catheter system. FIG. 2C also illustrates an instrument assembly (108) that includes a combination of steerable elongate instrument assemblies or catheter systems which are comprised of respective control units or splayers (222 and 232) and corresponding associated elongate instruments or catheters (224 and 234). FIG. 2D illustrates another embodiment of an instrument assembly (108) that includes a combination of steerable elongate instrument assemblies and catheter systems which may also include respective control units or splayers (242 and 252) and corresponding associated elongate instruments or catheters (244 and 254).

Basic Structure of a Steerable Instrument

FIG. 3A illustrates a cross-sectional view of a section or portion of a flexible and steerable elongate instrument or catheter (300) of an instrument assembly (108) in accordance with one embodiment. The steerable elongate instrument (300) may be substantially pliable or flexible such that when it is advanced into a patient, an operator or surgeon may easily manipulate the instrument (300) to conform, adopt, or match the shape or curvatures of the internal pathways (e.g., gastrointestinal tract, blood vessels, etc.) of the patient. As illustrated, the flexible and steerable elongate instrument or catheter (300) may be comprised of multiple layers of materials and/or multiple tube structures. For example, the elongate instrument (300) may includes an outer layer or outer tube (302), a main lumen, primary lumen, or central lumen (318) defined by an inner layer or inner tube (312), and minor, secondary, or peripheral lumens incorporated in the body of the elongate instrument (300) substantially between the outer layer (302) and the inner layer (312) where operational tubes (304), flexible tubes (306), push tubes (308), and support tubes (310) are disposed or contained. The lumen (318) may be used to deliver one or more surgical instruments or tools from the proximal portion of the elongate instrument (300) to the distal portion of the elongate instrument (300) where they maybe positioned and used to treat a target tissue structure inside a patient. The outer layer or outer tube (302) and the inner layer or inner tube (312) may be made of any flexible, pliable, or suitable polymer material or bio-compatible polymer material (e.g., nylon-12, plastic, Pebax®, Pellathane, Polycarbonate, etc.) or braided plastic composite structure. In some embodiments, outer layer or outer tube (302) and the inner layer or inner tube (312) may be one layer of material or one tube structure instead of separate layers of material or separate tube structures. Operational tubes (304) may not be actual tubes but may be the minor, secondary, or peripheral lumens or channels through the body of the outer layer or outer tube (302) or the operational tubes (304) may be separate operational tube strictures that are disposed inside the minor, secondary, or peripheral lumens or channels in the body structure of the outer layer or outer tube (302). The operational tubes (304) may be made of any suitable polymer material, bio-compatible polymer material or metallic material (e.g., polyimide, stainless steel or spiral cut stainless steel, Nitinol, etc.). The separate operational tubes (304) may be melted and/or braided into the wall of the minor, secondary, or peripheral lumens of the outer tube (302) or inner tube (312). The operational tubes (304) may provide a substantially slidable surface and interface for the flex tubes (306), such that the flex tubes (306) may slide substantially freely about the interior of the operational tubes (304) in a substantially decoupled configuration. In some embodiments, a distal end or portion of the flex tubes (306) may be fixedly coupled to the elongate instrument. In some variations, a proximal end or portion of the flex tubes may also be fixedly coupled to the elongate instrument (300) as in a passively controlled configuration of the flex tubes (306).

For example, in a passively controlled configuration, the flex tubes (306) may passively slide along the interior of the operational tubes as the elongate instrument or catheter (300) is navigated through the anatomy, articulated or steered. As will be discussed in more detail, the slidable interface between the flex tubes (306) and the operational tubes (304) together with buffer loops of the flex tubes in the control unit substantially decouple the flex tubes (306) from the elongate instrument or catheter (300). Because of the decoupled configuration of these two structures, articulation forces supported by the flex tubes may be decoupled from at least a portion of the catheter body or structure (300). As a result of decoupling the flex tubes (306) from at least a portion the catheter body or structure, articulation forces applied to articulate or steer the distal portion of the elongate instrument or catheter (300) may not be transmitted through or along the body of the elongate instrument from the distal portion to the proximal portion of the elongate instrument, for example. Consequently, as described in this example, articulation forces may be prevented or minimized from compressing the proximal portion of the elongate instrument or catheter body; such compression if allowed to occur, may affect the stiffness or bending stiffness of the proximal portion of the catheter. In addition, this decoupling of the articulation forces for the elongate member allows that changes in the shape or length of the elongate member as it is navigated through the anatomy may not have any impact or minimal impact on the articulation performance of the distal section of the elongate instrument. As will be also discussed in more detail, in some embodiments, the flex tubes (306) may also be utilized as support or reinforcing structures to vary or change the stiffness and/or bend radius of at least a portion of the catheter. In particular, the flex tubes (306) may be very effective support or reinforcing structures when they are compressed and stiffened. In other words, an elongate instrument (300) or a section of the elongate instrument without any flex tubes (306) may be substantially flexible. With the introduction of one or more flex tubes (306) into the body of the elongate instrument or a section of the elongate instrument, the elongate instrument or the section of the elongate instrument with the flex tubes (306) may become less flexible; even though the flex tubes (306) are flexible, they still have inherent axial stiffness, lateral stiffness, and bending stiffness. When the flex tubes (306) are compressed, such as using pull wires to apply a compressible force or load to the flex tubes, for example, they may become substantially more stiff laterally, such that the stiffened structures may affect or alter the stiffness and/or bend radius of at least a portion of the catheter where the flex tubes (306) are located. Accordingly, the flex tubes (306) may be utilized to vary or change the stiffness and/or bend radius of a portion or certain portion of the catheter by changing the positioning or placement of the flex tubes (306) in the elongate instrument (300). For example, the flex tubes (306) may be moved from one portion of the elongate instrument or catheter to another portion of the catheter. The portion from which where the flex tubes (306) were moved may become substantially more flexible or pliable without the flex tubes (306). Whereas, the portion to which where the flex tubes (306) were moved to may become substantially more stiff or less flexible or pliable. Consequently, the changes of stiffness along various portions of the elongate instrument or catheter may substantially affect the bend radius of at least a portion of the elongate instrument as pull wires are operated to articulate or steer the elongate instrument.

Referring back to the structural make up of the steerable instrument (300) as illustrated in FIG. 3A, the flex tubes (306) may be made from a coil of wire, a stack of rings, or a tube with spirally cut features. As may be appreciated, a substantially stiff tube may become less stiff or more flexible or more pliable as a spiral cut or spirally cut feature is imparted onto a substantially stiff tube. The tube may be made from a of a high durometer plastic such as Peek™ or stainless steel or other suitable material. One of the features of the flex tube (306) is that it may provide structural support to the elongate instrument (e.g., axial and lateral support) as well as being substantially flexible (e.g., able to bend in various directions and orientations). In some embodiments, the flex tubes (306) may be constructed from one continuous coil of wire, e.g., coil tube. In some other embodiment, the flex tube (306) may be constructed from a stack of rings, e.g., ring tube. For a ring tube, the rings may be stacked, grouped, or maintained together in any suitable manner. In some of the embodiments, the rings may be stacked, grouped, or maintained together by a substantially flexible sleeve, sheath, membrane, or covering. The coil of wire or rings may be made from a polymer material or metallic material. For example, a coil wire or rings may be made from stainless steel, Nitinol, etc. The coil wire may be made from a round stock or a flat stock or a stock having any cross-section or profile. Similarly, the rings of the ring tube may be made from a round stock or a flat stock or a stock having any cross-section or profile. In accordance with embodiments of the present invention, the flex tubes (306) may be generally constructed from a substantially tightly wound coil of wire or a stack of rings.

Still referring to FIG. 3A, the support tubes (310) may be made of any suitable polymer material, bio-compatible polymer material, or metallic material (e.g., polyimide, stainless steel, Nitinol, etc.). The inner layer or inner tube (312) may be made of any suitable polymer material or bio-compatible polymer material (e.g., nylon-12, plastic, Pebax®, Pellathane, Polycarbonate, etc.). In addition, the elongate instrument (300) may include a control ring (316) that may be secured near a distal portion of the elongate instrument (300). In various embodiments, the proximal end or portion of one or more pull wires (314) may be operatively coupled to various mechanisms (e.g., gears, pulleys, etc.) of a control unit or splayer of the instrument assembly (108). The pull wire (314) may be a metallic wire, cable or thread, or it may be a polymeric wire, cable or thread. The pull wire (314) may also be made of natural or organic materials or fibers. The pull wire (314) may be any type of suitable wire, cable or thread capable of supporting various kinds of loads without deformation, significant deformation, or breakage. The distal end or portion of one or more pull wires (314) may be anchored or mounted to the control ring (316), such that operation of the pull wires (314) by the control unit or splayer may apply force or tension to the control ring (316) which may steer or articulate (e.g., up, down, pitch, yaw, or any direction in-between) certain section or portion (e.g., distal section) of the elongate instrument (300). In other embodiments, no control ring may be used, instead the distal portion of the pull wires may be attached directly to a section or portion of the elongate instrument (300) where it may be steered, articulated, or bent. The wires may be crimped, soldered, welded or interlocked in any suitable manner to a specific location on a bending section or portion of the elongate instrument (300). The control ring (316) or the attachment point(s) may be located at any location, section, portion, or region along the length of the elongate instrument (300). Operation of the pull wires (314) may steer or articulate any of the location, section, portion, or region of the elongate instrument (300), which may in effect provide or define various bend radii for the articulated portion of the elongate instrument (300). In addition, in some embodiments there may be more than one control ring (316) mounted or installed to the elongate instrument (300) or more than one control wire attachment control locations, sections, or portions for controlling, steering, or articulating more than one section or portion of the elongate instrument (300). As will be described further, the flexible and steerable elongate instrument (300) having more than one control rings (316) or more than one control sections may be steered, articulated, or deflected into various complex shapes or curvatures (e.g., “S” curved shapes or “J” curved shapes, etc.). For example, the steerable elongate instrument (300) may be steered, articulated, or deflected into various complex shapes or curvatures that may conform to various complex shapes or curvatures of internal pathways of a patient to reach a target tissue structure of an organ inside the patient.

In some embodiments, one or more portions of the flex tubes (306) may be incorporated or coupled to the wall of the catheter (300) and such incorporation or coupling may be used for multiple functional purposes. For example, the coupling of the flex tubes (306) to the elongate instrument (300) may be used to support articulation forces as the elongate instrument or catheter is steered or articulated. As one or more of the pull wires (314) are operated by the control unit to steer or articulate the elongate instrument (300), the articulation or steering forces may be substantially transmitted along the body of the elongate instrument (300) from the portion (e.g., distal portion) of the elongate instrument (300) where the distal end or portion of the pull wires (314) may be anchored to the proximal portion of the elongate instrument (300). Since the flex tubes (306) are incorporated or coupled to the wall of the elongate instrument (300) and the flex tubes (306) are substantially configured to support axial loading, the articulation or steering loads may be decoupled from the elongate instrument (300) at the point or location where the flex tubes (306) are incorporated or coupled to the wall of the elongate instrument (300). Hence, the proximal portion of the elongate instrument may be substantially unaffected by the articulation or steering of the particular section or portion (e.g., distal section or portion) of the elongate instrument (300). The proximal portion of the elongate instrument may remain substantially flexible and pliable even when a particular portion (e.g., distal portion) of the elongate instrument is being articulated or steered. As such, an operator or surgeon may easily manipulate the elongate instrument (300) and urge it to conform, adopt, or match the various shape or curvatures of the internal pathways of a patient while the elongate instrument is being advanced and steered to reach various tissue structures or target sites inside a patient. In another example or application of the elongate instrument (300), the flex tubes (306) may be used as a structural support member to the catheter (300); in particular, when the flex tubes are stiffened by tensioning pull wires that may be attached to the flex tubes (306). In such application, the flex tubes (306) may support not only axial forces or loads, but also lateral forces or loads. As such, the flex tubes may increase the lateral as well as bending stiffness of at least a portion or section of the elongate instrument (300). In addition, the flex tubes (306) may also affect the bending radius of at least a portion or section of the elongate instrument (300) as the elongate instrument is steered, articulated, or manipulated.

FIG. 3B illustrates another cross-sectional view (View 1-1) of a section or portion of a steerable elongate instrument or catheter (300). As illustrated in FIG. 3B, the components of the elongate instrument (300) may be contained within or between the outer layer of material or outer tube (302) and the inner layer of material or inner tube (312). A primary, main, central, or working lumen (318) may be provided or defined by the inner layer of material or inner tube (312). The main lumen or central lumen (318) may be used to pass surgical instruments from the proximal end to the distal end of the elongate instrument (300) for performing various minimally invasive surgical procedures. Many of the components of the elongate instrument (300), e.g., operational tubes (304), flexible tubes (306), push tubes (308), and support tubes (310), are disposed within the minor, secondary, or peripheral lumens in the body structure of the elongate instrument, as illustrated in FIG. 3A and FIG. 3B. In some embodiments, one or more pull wires (314) may be disposed within lumens of the support tubes (310), lumens of the flex tubes (306), and lumens of the push tubes (308). As illustrated in FIG. 3A, the distal end or portion of the support tubes (310) may be secured or anchored near the distal portion of the elongate instrument (300) and the proximal end of the support tubes (310) may be slidably coupled to the distal end or portion of the flex tubes (306). In one embodiment, the distal portion of the flex tubes (306) may be secured at respective anchor points or regions (320) of the elongate instrument (300). Anchoring the flex tubes (306) to the elongate instrument (300) may provide the connections or couplings that allow force or load to be transferred from the flex tubes (306) to the elongate instrument (300) when force or load is applied to the flex tubes. For example, in some embodiments the flex tubes (306) may be actively controlled, that is one or more push tubes (308) or control members (308) may be configured to push against respective flex tubes (306). The applied force from the push tubes or control members (308) may be transmitted by way of the anchoring points (320) through the flex tubes (306) to the elongated instrument (300). In this way, at least a portion of the elongate instrument (300) may be steered or shaped by the push tubes or control members (308). Similarly, articulation or steering forces or loads may be transferred or coupled at the anchor points (320) from one portion (e.g., distal portion) of the elongate instrument (300) to the flex tubes (306), such that the flex tubes (306) may act as load bearing support elements for another portion (e.g., proximal portion) of the elongate instrument (300) where the force or load may be decoupled or not transmitted. In other words, the anchor points (320) may function as coupling points from one portion (e.g., distal portion) of the elongate instrument (300) to the flex tubes (306) where force or load may be transferred from one portion (e.g., distal portion) of the elongate instrument to the flex tubes. Similarly, the anchor points (320) may also function as decoupling points between one portion (e.g., distal portion) of the elongate instrument (300) to another portion (e.g., proximal portion) of the elongate instrument (300) where force or load may be decoupled or not transferred from one portion (e.g., distal portion) of the elongate instrument to another portion (e.g., proximal portion) of the elongate instrument. As will be discussed in more details, the location of the anchor points (320) may be varied to control the radius of curvature of a bending section of the elongate instrument (300) as the elongate instrument is articulated or steered. In some embodiments, the flex tubes (306) may be anchored at substantially the same points or regions of the elongated instrument (300). In some embodiments, the flex tubes (306) may be anchored at substantially different points or regions of the elongate instrument (300) to affect the bend radius of various portions of the elongate instrument (300) and/or various directions of steering or bending. The flex tubes (306) may be secured to the elongate instrument (300) in any suitable manner. In some embodiments, the distal portion of the flex tubes (306) may be fused with the material of the outer layer or outer tube (302), such as by thermal fusion. Similarly, the material of the outer layer or outer tube (302) may be fused to the flex tubes (306). For example, the flex tubes (306) may be fused to the outer layer or outer tube (302) at various places where it is not covered by the operational tubes (304), as illustrated in FIG. 3A. In some embodiments, the elongate instrument may be configured with displacement control of the flex members (306). That is a flex tube (306) may not be fixedly coupled to the elongate instrument, instead it may be displaced along the length of the elongate instrument (300). Once the flex tube (306) is displaced to a desired location, the distal portion of the flex tube (306) may be secured or coupled to the elongate instrument (300) by a deployable and retractable anchor. The displacement of proximal portion of the flex tube (306) may be controlled by the push tube or control member (308). The deployable anchor may be deployed to couple the flex tube (306) to a particular anchor point at a particular location on the elongate instrument. The anchor may also be retracted such that the flex tube (306) may be disengaged or separated from the elongate instrument (300) such that it may be displaced to a different location along the elongate instrument (300).

Passively Controlled Flex Member

As illustrated in FIG. 4A, an elongate instrument (300) with passively controlled flex members (300) may be similarly configured as the elongate instrument structure illustrated in FIG. 3A with the exception that the proximal portion of the flex members (300) may be fixedly coupled to the body of the elongate instrument, the control unit or splayer, or some other structural element or component. In some embodiments, the push tube or control member (308) may not be included as a component of the elongate instrument (300) for a passively controlled flex member. In the passively controlled configuration, the flex members (306) may include a service or buffer loop (402), as more clearly illustrated in FIG. 4B. The service loop or buffer loop (402) on the flex members (306) may provide the extra service length or buffer length needed for articulation as the elongate instrument (300) is pushed through the anatomy, articulated or steered.

As the elongate instrument is pushed through the anatomy, steered or articulated, the support tubes (310) in the distal section may slide along the flex tubes (306) as indicated by the arrows in FIG. 4C. The support tubes (310) may provide a lumen or path for the pull wires (314) to connect to the distal section of the catheter. The support tubes (310) may also provide some amount of structural rigidity or support to the distal portion of the elongate instrument (300). In some embodiments, the elongate instrument (300) may not include any support tubes (310). In some embodiments, one or more flex tubes (306) may be extended further into the distal portion of the elongate instrument (300) to provide some structural rigidity or support to the distal portion of the elongate instrument. In some embodiments, the flex tubes (306) may be substantially more stiff or more rigid than the support tubes (310), such that when one or more flex tubes (306) are used as support structures to reinforce the distal portion of the elongate instrument (300), the distal portion of the elongate instrument may be substantially more stiff or more rigid than when it is supported by the support tubes (310). In some embodiments, the flex tube (306) may provide substantially the same or similar stiffness or structural support as the support tubes (310), such that there may not be any significant difference if the flex tubes (306) or support tubes (310) are used to provide structural support to the distal portion of the elongate instrument (300). In some embodiments, the flex tubes (306) may be substantially more flexible than the support tubes (310), such that the distal portion of the elongate instrument may be substantially more flexible or less rigid than when it is supported by the flex tubes (306).

Referring back to FIG. 4A, the flex tubes (306) may be slidably coupled to the operational tubes (304) while fixed at the distal end (320). As the elongate instrument (300) is steered or articulated, or as the catheter is advanced through the natural curvature of the body lumens, the flex tubes (306) may slide along the operational tubes (304) as indicated by the arrows illustrated in FIG. 4D. In one scenario, for example, the elongate instrument (300) may be steered by operating or applying tension to one of the pull wires (e.g., 314A) through operation of one or more gears and/or pulleys in the control unit or splayer. The tension on one of the pull wires (e.g., 314A) may cause the elongate instrument (300) to bend, as illustrated in FIG. 4D. The inside edge or inside region of the bend may be contracted or foreshortened, while the outside edge or outside region of the bend may be lengthened or stretched. The bend of the elongate instrument as described may cause one of the flex tubes (e.g., 306A) to slide “out” near the proximal portion of the elongate instrument (300) at the contracted or foreshorten edge or region. In this same example, another one of the flex tubes (e.g., 306B) may slide “in” near the proximal portion of the elongate instrument (300) at the lengthened or stretched edge or region, as illustrated in FIG. 4D. In order to accommodate the sliding of “in” and “out” of the flex tubes (306), the flex tubes may include a service loop or buffer loop (402) to allow for these “in” and “out” displacements or movements of the flex tubes (306). As discussed, the flex tubes (306) may be passively constrained or restrained. The flex tubes (306) may be constrained or restrained by being coupled to the elongate instrument (300), the control unit, or splayer. In addition, the flex tubes (306) may be constrained or restrained by hard-stops, tethers, etc. In some embodiments, the operational tubes (304) may be configured or allowed to float or slide substantially freely relative to the outer layer or outer tube (302). In some other embodiments, the operational tubes (304) may not be configured or allowed to float or slide substantially freely relative to the outer layer or outer tube (302).

Actively Controlled Flex Member

In some embodiments, the flex member (306) of an elongate instrument may be actively controlled. For example, the distal portion of the flex member (306) may be coupled to the body of an elongate instrument, while the proximal portion of the flex member (306) may be displaced or moved by various control mechanisms or members of the elongate instrument assembly or system. In some embodiments, the proximal portion of the flex members (306) may be displaced by push tubes or control members. The push tubes or control members may be operated by mechanisms of an instrument assembly, control unit, or splayer of an elongate instrument assembly or catheter system. A control unit or splayer in an elongate instrument assembly or catheter system may include drive mechanisms that are configured to operate or drive the push tubes or control members. In one example, as illustrated in FIG. 5A through 5D, the drive mechanisms in a control unit (502) of a catheter system (500) may include racks (508) and pinions (510) for operating or driving the push tubes (506) or control members (506). In some embodiments, the pinions (510) may be operated by output torque provided by the instrument driver (106) of a robotic or telerobotic surgical system (100). In some embodiments, the pinions (510) may be operated by output torque provided by various mechanical or manually operated systems. Other drive mechanisms may also be configured to operate or drive the push tubes, e.g., rotary gears, worm gears, linear gears, etc. FIG. 5A illustrates an exposed view of a control unit or splayer (502) of an elongate instrument assembly or catheter system (500). A close-up view (View 2-2) of the control unit (502) is illustrated in FIG. 5B. As illustrated in FIG. 5B in View 2-2, push tubes (506) or control members (506) may be controlled or driven by racks (508) and pinions (510) in a “forward” or “backward” manner, movement or displacement, so as to apply or release force exerted onto the flex tubes (506) of a steerable elongate instrument or catheter (504). As the racks (508) are driven “forward”, the flex tubes (506) may be driven forward and they may also be compressed in the axial direction. The “forward” displacement of the flex tubes (506) may apply an axial load to the distal section of the elongate instrument or catheter (504). This axial load may cause the distal section of the catheter (504) to bend, deflect, steer, or articulate at a particular position or location of the catheter. Since the flex tubes (506) may be anchored or secured at the distal section, compression force applied at the proximal section by the racks (508) may cause at least a portion, e.g., distal portion, of the elongate instrument or catheter (504) to bend, deflect, steer, or articulate in response to the compression force exerted by the racks (508) and form a particular induced shape or orientation. Accordingly, active control of the push tubes (506) may allow “shaping” or putting the elongate instrument or catheter (504) into various shapes or curvatures. The elongate instrument or catheter (504) or portion (e.g., proximal portion) of the catheter (504) may be induced and then locked in place by the push tubes (506) into various shape or curvatures that may substantially match the natural pathways or anatomy where the elongate instrument or catheter may be used in a minimally invasive procedure. In addition, another portion (e.g., distal portion) of the catheter may be articulated or steered by pull wires to navigate the catheter (504) through torture pathways inside the patient.

FIG. 5C illustrates another exposed view of a catheter system (500). As illustrated in FIG. 5C, drive pins (512), which may be engaged to a torque output system (e.g., instrument driver), provide the necessary torque or motion to operate the pinions (510) for controlling or driving the racks (508) in a “forward” or “backward” manner, movement, or displacement. The forward and backward movements of the racks (508) may be used to actively control or operate the push tubes (506). FIG. 5D illustrates a close-up view (View 3-3) of the racks (508) and push tubes (506). The drive mechanisms in the instrument driver may operate each set of racks (508) and pinions (510) independently or in concert in a coordinated manner. As such, the push tubes or control members (506) may be operated independently or in concert in a coordinated manner to apply or release force or tension on the flex tubes (506).

FIG. 6A through FIG. 6C illustrate the operation of a substantially flexible and steerable elongate instrument in accordance with one embodiment. FIG. 6A illustrates an elongate instrument (600) of an instrument assembly in a substantially neutral state. In this example, the elongate instrument (600) includes an outer body (602), two sets of support tubes (not shown), operational tubes (604A and 604B), flex tubes (606A and 606B), and pull wires (608A and 608B). Each set of support tubes, operational tubes (604A and 604B), flex tubes (606A and 606B), and pull wires (56A and 568B) may be substantially axially aligned, and the pull wires (608A and 608B) may be coupled to a control ring (not shown) or mounting points that are located at the distal section or portion of the elongate instrument (600). As illustrated in FIG. 6A, in the neutral state the flex tubes (606A and 606B) and pull wires (608A and 608B) may extend out of the operational tubes (604A and 604B) at about the same amount or distance. As the substantially flexible and steerable elongate instrument (600) is advanced into the anatomy and natural pathway (e.g., blood vessel, gastrointestinal tract, etc.) of a patient, it may take on the shape of the natural pathway, as illustrated in FIG. 6B. In this example, the proximal section (610) of the elongate instrument may be bent at a curvature induced by the natural pathway (e.g., blood vessel, gastrointestinal tract, etc.), while the distal section (620) may remain relatively straight or in a substantially neutral state. Due to the bend at the proximal section (610), the flex tube (606A) and pull wire (608A) may slide “out” of the operational tube (604A) near the inside edge or inside region of the bend as it may be contracted or foreshortened, as indicated by the arrow illustrated in FIG. 6B. At the same time, due to the bend at the proximal section (610), the flex tube (606B) and pull wire (608B) may slide “in” to the operational tube (604B) near the outside edge or outside region of the bend as it may be lengthened or stretched, as indicated by the arrow illustrated in FIG. 6B. As may be appreciated, it may be advantageous to maintain the induced shape or curvature of the proximal section (610) of the elongate instrument (600) and at the same time articulate or steer the distal section (620) of the elongate instrument (600) to treat a target site or toward a different direction down the natural pathway. As illustrated in FIG. 6C, the shape or curvature of the proximal section (610) of the elongate instrument (600) may be maintained or locked by securing the distal ends of the flex tubes (606A and 606B) into the position they have acquired due to the induced shape or bend of the proximal section (610). The flex tubes (606A and 606B) may be locked in place by using the active control feature of the instrument assembly provided by the various mechanisms (e.g., rack and pins, drive gears, etc.) in the control unit or splayer. While the elongate instrument (600) may be inherently substantially flexible, the elongate instrument or portion of the elongate instrument may become substantially stiff or rigid when the flex tubes are compressed or locked through active control. Once the flex tubes are locked in place, they may become substantially stiff or rigid structures or platforms. As the flex tubes have been locked in place to maintain the induced shape or curvature of the proximal section (610), pull wires (608A and 608B) may be operated to steer or articulate the distal section (620) of the elongate instrument (600). In this example, pull wire (608B) may be pulled or tensioned, as indicated by the arrow illustrated in FIG. 6C, to steer the distal section (620) in a substantially opposite direction of the bend in the proximal section (610). The pull wire (608A) may be relaxed, as indicated by the arrow illustrated in FIG. 6C, to accommodate for the bend at the outside edge or outside region of the bend of the distal section (620). In addition, the bending force or load of the distal section (620) may be substantially absorbed or transferred from the elongate instrument through the flex tube attachment points and then to the flex tubes (606A and 606B), which may be further transferred to the control unit or splayer of the instrument assembly. The proximal section (610) of the elongate instrument (600) may not be affected by the steering or articulation forces applied by the pull wire to steer the distal section (620) of the elongate instrument (600).

In another example, as illustrated in FIG. 7A through FIG. 7C, the proximal section (610) of the elongate instrument may be bent at a curvature induced by the bending, steering, or articulation of the distal section (620) of an elongate instrument (600). FIG. 7A illustrates an elongate instrument (600) of an instrument assembly in an initial substantially neutral state. In this example, the elongate instrument (600) includes an outer body (602), two sets of support tubes (not shown), operational tubes (604A and 604B), flex tubes (606A and 606B), and pull wires (608A and 608B). Each set of support tubes, operational tubes (604A and 604B), flex tubes (606A and 606B), and pull wires (608A and 608B) may be substantially axially aligned, and the pull wires (608A and 608B) may be coupled to a control ring (not shown) or mounting points that are located at the distal section or portion of the elongate instrument (600). As illustrated in FIG. 7A, in the neutral state the flex tubes (606A and 606B) and pull wires (608A and 608B) may extend out of the operational tubes (604A and 604B) at about the same amount or distance. The substantially flexible and steerable elongate instrument (600) may be steered or articulated at the distal section by operation of the pull wires (608A and 608B), as illustrated in FIG. 7B. In this example, the proximal section (610) of the elongate instrument may be bent at a curvature induced by the bending, steering or articulation at the distal section (620). The induced bend and curvature at the proximal section (610) may be locked in place by using the active control feature of the instrument assembly provided by the various mechanisms (e.g., rack and pins, drive gears, etc.) in the control unit or splayer as previously described. While the elongate instrument (600) may be a substantially flexible instrument, the proximal section (610) may become substantially stiff or rigid as the flex tubes (606A and 606B) are locked in place, and proximal section (610) may become a substantially rigid platform to support the manipulation or articulation of the substantially flexible distal section (620). As a result, the flex tubes may act as support structures of the elongate instrument. The ability to lock various sections of the elongate instrument into particular shapes or curvatures by means of the flex tubes allow the elongate instrument to be manipulated into substantially complex shapes or curvatures (e.g., “S” shaped curves, “J” shaped curves, etc.). In this example, pull wire (608B) may be pulled or tensioned, as indicated by the arrow illustrated in FIG. 7C, to steer the distal section (620) in a substantially opposite direction of the bend in the proximal section (610).

In other embodiments of an elongate instrument where flex tube or similar control or support structure may not be used, operating or tensioning a pull wire on the outside edge of a bend may cause the elongate instrument to rotate or twist as the pull wire may tend to rotate the distal section of the elongate instrument until the pull wire is at the inside edge of the bend; this rotation or twist phenomenon or occurrence is known, as curve alignment. Embodiments of the present invention may substantially eliminate this problem by providing support structures such as flex tubes that could prevent curve alignment and substantially prevent or eliminate unwanted rotation or twist of the catheter. In other words, the pull wires, flex tubes, and the distal anchor points of the pull wires at the control ring or the body of the elongate instrument may all be substantially aligned, such that operating or tensioning of the pull wires would allow the elongate instrument to bend in a substantially aligned or neutral configuration with the longitudinal axis of the pull wire and flex tube. In this configuration, there may not be any component or vector of force or load that could cause the elongate instrument to rotate or twist resulting in curve alignment as the elongate instrument is steered or bent. FIG. 8A and FIG. 8B illustrate one embodiment of an elongate instrument or catheter (800) that substantially eliminate or prevent curve alignment and the catheter may be biased, steered, or articulated in specific planes, e.g., X-Plane, Y-Plane, Z-Plane, of articulation by using flex tubes as support structures or “backbones” that may be in substantial alignment with a neutral axis. As illustrated in FIGS. 8A and 8B, the pull wires may be substantially aligned with the neutral axes, e.g., in the X-Y Planes. In FIG. 8A, as a pull wire is operated (indicated by the arrow) to steer the elongate instrument, the flex tube supports the pull wire, maintain its alignment to the longitudinal axis, and prevent it from moving to the inside edge of the bend, which may produce a force vector that could cause the elongate instrument to twist or rotate. In this example, the operation of the pull wire causes the distal section of the elongate instrument to be steered or articulated in a substantially upward movement, e.g., the direction or vector of articulation is in the Y-Plane. Similarly, as illustrated in FIG. 8B, as a pull wire is operated (indicated by the arrow) to steer the elongate instrument, the flex tube supports the pull wire, maintain its alignment to the longitudinal axis, and prevent it from moving to the inside edge of the bend, which may produce a force vector that could cause the elongate instrument to twist or rotate. In this example, the operation of the pull wire causes the distal section of the elongate instrument to be steered or articulated in a substantial sideway or rightward movement, e.g., the direction or vector of articulation is in the X-Plane.

As described, embodiments of the present invention may allow a flexible and steerable elongate instrument to execute various movements necessary to form variable or changeable shapes and curvatures. For example, FIG. 9 illustrates one embodiment in which a complex “S” shaped curvature may be formed with an elongate instrument (900). In this example, the elongate instrument (900) may include a first flex tube (906-1) which may be disposed inside a lumen of a first operational tube (904-1). The first operational tube (904-1) may terminate near a first anchor point or region (920-1), where the first flex tube (906-1) may be secured, fused, or bonded to the material of the elongate body (900), as illustrated in a first detail view (View 4-4) of FIG. 9. A first pull wire (914-1) may be disposed through a lumen of the flex tube (906-1) and a first support tube (910-1), wherein the proximal end of the first pull wire (914-1) may be operatively coupled to a control unit or splayer (not shown) and the distal end of the first pull wire (914-1) may be anchored to a control ring (916-1) or an anchor point on the body of the elongate instrument (900), as illustrated in a second detail view (View 5-5) of FIG. 9. The support tube (910-1) may be slidably coupled to the first flex tube (906-1), such that it may slide along the surface of the first flex tube as the elongate instrument is steered or articulated. The elongate instrument (900) may include a second flex tube (906-2) which may be disposed inside a lumen of a second operational tube (904-2). The second operational tube (904-2) may terminate near a second anchor point or region (920-2), where the second flex tube (906-2) may be secured, fused, or bonded to the material of the elongate body (900), as illustrated in the second detail view (View 5-5). A second pull wire (914-2) may be disposed through a lumen of the second flex tube (906-2) and a second support tube (910-2), wherein the proximal end of the second pull wire (914-2) may be operatively coupled to a control unit or splayer (not shown) and the distal end of the second pull wire (914-2) may be anchored to a second control ring (916-2) or an anchor point on the body of the elongate instrument (900), as illustrated in FIG. 9. The second support tube (910-2) may be slidably coupled to the second flex tube (906-2), such that it may slide along the surface of the second flex tube as the elongate instrument is steered or bent. Although two flex tubes and associated components are illustrated in FIG. 9, additional number of flex tubes and associated components, e.g., 2 or more sets of flex tubes and associated components, may be used to steer and control the movement as well as the shape of the elongate instrument.

As illustrated in FIG. 9, the first or lower portion of the “S” may be formed by the proximal portion of the elongate instrument (900). The lower portion of the “S” may be obtained by operating the first pull wire (914-1) to steer the proximal portion of the elongate instrument (900) into a curvature that resembles the shape of the lower portion of the “S” shape. The lower portion of the “S” shape formed by the proximal portion of the elongate instrument may be locked in place by locking the second flex tube (906-2) in the position it has acquired by various control means (e.g., active control mechanisms of the control unit or splayer). Once the proximal portion of the elongate instrument has been locked in place, the second pull wire (714-2) may be operated to steer or bend the distal portion of the elongate instrument (900) into a curvature that resembles the upper portion of the “S” as illustrated in FIG. 9.

Another complex shape may be formed by an elongate instrument in accordance with another embodiment. FIG. 10 illustrates a complex “J” shaped curvature formed by an elongate instrument (1000). In this example, the elongate instrument (1000) may include two set of flex tubes and their associated components. As illustrated in FIG. 10, the “J” shaped curvature may be formed from three sections of the elongate instrument (1000). The first section (1002-1) may be substantially straight to form the straight portion of the “J”, the second section (1002-2) may form a first bend section of the first curvature or initial curvature of the “J”, and the third section (1002-3) may form the second bend of the second or final curvature of the “J”. As illustrated in FIG. 10, the elongate instrument (1000) may include two flex tubes (1006-1 and 1006-2). The first flex tube (1006-1) may operate as a support structure to provide the support (e.g., lateral stiffness or support) necessary to form or maintain the straight portion of the “J”. Similar to the construction of other embodiments as previously described, the distal end of flex tube (1006-1) may be anchored to the elongate body near the distal section of first section (1002-1) of the elongate body where it may not be covered by the operational tube (1004-1). Active control as previously described may be used to apply force or load to compress the flex tube (1006-1), such that the flex tube may become a substantial rigid or stiff structure. Since compression force was applied to the flex tube (1006-1) when it was in a substantially neutral state without having been deflected, steered, or articulated, the flex tube (1006-1) may be maintained or stiffened in its neutral or substantially straight configuration. In its compressed or substantially stiffened or rigid state, the flex tube (1006-1) may be used to support the deflection or articulation of the second section (1002-2) of the elongate instrument. The second section (1002-2) may be deflected or articulated by operating the pull wire (1014-1). The distal end of the pull wire (1014-1) may be anchored to a control ring (1016-1) or an anchoring point near the distal portion of the second section (1002-2). The proximal end of the pull wire (1014-1) may be operatively coupled to a control unit or splayer (not shown) that operates the pull wire. Once the desired curvature of the second section (1002-2) is achieved, the shape of the curvature may be locked in place by compressing and/or locking the second flex tube (1006-2) in place using active control as previously described. The distal end of the second flex tube (1006-2) may be anchored to the elongate instrument near the distal portion of second section (1002-2) where it may be exposed out of the second operational tube (1004-2). Once the second flex tube (1006-2) is locked in place and becomes a substantially stiffened or rigid structure, the second pull wire (1014-2) may be operated to steer or articulate the third section (1002-3) into the desired curvature to form the “J” shape. The distal end of the second pull wire (1014-2) may be anchored to the second control ring (1016-2) or to an anchor point on the elongate body near the distal portion of the third section (1002-3). The proximal end of the second pull wire (1014-2) may be operatively coupled to a control unit or splayer (not shown) that operates the pull wire. Although two examples of complex shapes or curvatures may be formed by a flexible and steerable elongate body with variable or changeable shape control and support elements as illustrated and described, many other complex shapes or curvatures may be form by an elongate body in accordance with various embodiments of the present invention.

Displaceable Flex Member

FIG. 11A illustrates another embodiment of a flexible and steerable elongate instrument in accordance with another embodiment of the present invention. In this embodiment, the flex tubes (1106-1 and 1106-2) may be allowed to slide along the length of the elongate instrument (1100). That is, the flex tubes (1106-1 and 1106-2) may not be fixedly secured to the elongate instrument (1100), instead the flex tubes may include a deployable and retractable anchor that allows the flex tubes to be displaced. As such, the position of the flex tubes (106-1 and 1106-2) may be changed substantially along the length of the elongate instrument (1100). The positions of the flex tubes (1106-1 and 1106-2) may be changed by operating various pull wires (1124-1 and 1124-2), push tubes (not shown), and active control elements. Pull wires (1124-1 and 1124-2) may be secured near the distal portion of the flex tubes (1106-1 and 1106-2), as illustrated in detail view (View 6-6), and the pull wires (1124-1 and 1124-2) may be used to control the displacement of the flex tubes. The other pull wires (1114-1 and 1114-2) may be extended and coupled to a control ring or the distal portion of the elongate instrument for steering or articulating the distal section of the elongate instrument. The pull wires may be flat wires, round wires, or wires having any suitable shape, cross section, or profile. Because the flex tubes (1106-1 and 1106-2) may not be secured, they may be moved or pushed further toward the distal portion of the elongate instrument (1100) by the respective push tubes or pulled back toward the proximal portion of the elongate instrument (1100) by the respective pull wires (1124-1 and 1124-2). The ability to move the flex tubes along the length of an elongate instrument provides greater variability and control of the possible shapes or curvatures that may be formed with the elongate instrument. In addition, the displacement of the flex tubes may also change the stiffness (e.g., lateral stiffness, bending stiffness) of at least a portion of the elongate instrument. The displacement of the flex tubes as it may affect the stiffness of at least a portion of the elongate instrument may also change or affect the radius of curvature of a least a portion of the elongate instrument as the elongate instrument is articulated or steered. By using the drive mechanisms in the control unit or splayer, the flex tubes (1106-1 and 1106-2) may be moved separately or in concert in a coordinated manner.

FIG. 11B and FIG. 11C illustrate one example of moving or displacing the flex tubes to alter the variability, shape, or curvature of an elongate instrument (1100) as well as an angle of trajectory (α) between two sections or portions of the elongate instrument (1100). As illustrated in FIG. 11B, the flex tubes (1106-1 and 1106-2) may be positioned along the length of the elongate instrument (1100) up to the location near the distal portion of the first section (1102-1). As illustrated in FIG. 11C and indicated by the first set of arrows (11C-1), the flex tubes (1106-1 and 1106-2) may be moved back toward the proximal end of the elongate instrument (1100). As illustrated, the first section (1102-1) of the elongate instrument (1100) may have become substantially shorter as compared to its initial state as illustrated in FIG. 11B when the same or substantially the same amount of force may be applied to steer or articulate the distal end or portion (1102-2) of the elongate instrument (1100). Correspondingly, the second section (1102-2) may have become substantially longer as compared to its initial state as illustrated in FIG. 11B. In addition, an angle of trajectory (α) between the first section (1102-1) and the second section (1102-2), as illustrated in FIG. 11B, may have also changed to a different angle of trajectory (α2), as illustrated in FIG. 11C. As the flex tubes (1106-1 and 1106-2) are moved back toward the proximal end of the elongate instrument (1100), the distal portion of the elongate instrument has lost some of it support and rigidity provided by the flex tubes (1106-1 and 1106-2). As a force or load is applied to steer or articulate the elongate instrument (1100), the less supported or more flexible distal portion of the elongate instrument may form a substantially larger or longer are or curvature as illustrated by a substantially larger or longer second section (1102-2) in FIG. 11C, than the are or curvature that may be obtained in its initial state illustrated in FIG. 11B. Accordingly, changing the position or location of the flex tubes along the length of an elongate instrument may allow the elongate instrument to change its characteristic properties of being able to form various shapes and/or curvatures as well as angle of trajectory (a) between two sections, portions or segments of elongate instrument. As illustrated in this example, displacement of the flex tubes (1106-1 and 1106-2) may alter the stiffness of a portion of the elongate instrument (1100). As the flex tubes (1106-1 and 1106-2) have certain amount of axial and lateral stiffness, displacing the flex tubes may affect the stiffness, e.g., axial and lateral stiffness, of at least a portion of the elongate instrument (1100). As may be appreciated, the variation or change of stiffness of a portion of the elongate instrument may affect the radius of curvature of at least a portion of the elongate instrument as force or load is applied to steer or articulate the elongate instrument. The displaced flex tubes may be locked in-place by using a deployable and retractable anchor in combination with push tubes or control members. The anchor then allows the flex tubes to serve as passive coils and absorb or bear the articulation loads and isolate or decouple the elongate body from the articulation loads. As such, the altered shape, curvature, and/or angle of trajectory (α) of the elongate instrument may be maintained for various purposes. For example, the altered shape, curvature, and/or angle of trajectory (α) may be maintained to facilitate advancement of the elongate instrument through a particular section of a tortuous pathway. In addition, the altered shape, curvature, and or angle of trajectory (α) may be maintain to facilitate advancement of certain objects, surgical instrument, etc. through a working lumen of the elongate instrument to a target tissue structure inside a patient.

The overall stiffness of at least a portion of the elongate instrument may be further altered or changed by compressing the flex tubes (1106-1 and 1106-2). The second set of arrows (11C-2) indicates that compression forces may be applied to stiffen the flex tubes (1106-1 and 1106-2) and provide substantially rigid structures to support steering or articulation of the second section (1102-2) of the elongate instrument (1100) by operating the pull wires (1114-1 and 1114-2) as indicated by the third set of arrows (11C-3) in FIG. 11C as the flex tubes (1106-1 and 1106-2) are supported by corresponding push tubes or control members (not shown).

Deployable and Retractable Anchor

FIG. 12A through FIG. 12F illustrate one embodiment of a deployable and retractable anchor for a displaceable flex tube or flex member of an elongate instrument. FIG. 12A illustrates the deployable and retractable anchor (1200) in its neutral state. That is, the anchoring mechanisms may not be deployed. FIG. 12B illustrates a close-up view of the deployable anchor (1200) in its neutral state, as shown in detail view (View 7-7). FIG. 12C illustrates the deployable anchor (1200) in its activated state. That is, the anchoring mechanisms are deployed or extended in engagement or coupling mode. FIG. 12D illustrates a close-up view of the deployable anchor (1200) in its activated state, as shown in detail view (View 8-8). Referring back to FIG. 12A, the deployable and retractable anchor (1200) may be coupled to a distal end or portion of a flex tube (1206). A distal end of an anchor wire or pull wire (1214-2) may be coupled to the deployable anchor (1200) and a proximal end of the anchor wire or pull wire (1214-2) may be coupled to a control unit (not shown). The control unit may be configured to operate the anchor wire (1214-2) to activate the deployable anchor (1200), such as tensioning the anchor wire, as well as operate the anchor wire (1214-2) to de-activate the deployable anchor, such as releasing the tension on the anchor wire. The anchor wire (1214-2) may be configured to operate the mechanisms of the deployable anchor, such as the distal anchor puck (1224) to operate various cam pins (1228) to travel along the cam pathways (1230) and then displace the anchoring cams (1222) to engage or disengage the deployable anchor (1200) from the body of the elongate instrument or catheter (not shown). The anchoring cams (1222) may be displaced upward to engage the body of the elongate instrument or downward to disengage the anchor (1200) from the body of the elongate instrument or catheter. A pull wire or control wire (1214-1) may be disposed through the flex member (1206) and the deployable anchor (1200) to a distal portion of the elongate instrument for steering or articulating the elongate instrument. As shown in more detail in FIG. 12E and FIG. 12F, distal anchor puck (1224) and proximal anchor puck (1226) support the anchor wire (1214-2). As the anchor wire is operated, e.g., tensioned by a control unit or splayer, the distal anchor puck (1224) may be displaced toward the proximal portion of the anchor (1200). The displacement of the anchor puck (1224) toward the proximal portion of the anchor (1200) may cause the cam pins (1228) to travel along the cam pathways (1230) which may cause the anchoring cams (1222) to be displaced upward to engage or couple the anchor (1200) to the body of the elongate instrument or catheter. The location of engagement or coupling becomes an anchoring point of the flex tube (1206) to the elongate instrument or catheter. In addition, as the anchor wire (1214-2) is operated or tensioned, the cam spring (1232) may be compressed in the activated state. When the anchor wire (1214) is operated to release the tension on the anchor wire (1214-2), the cam spring (1232) pushes the distal anchor puck (1224) toward the distal portion of the anchor (1200). The displacement of the anchor puck (1224) toward the distal portion of the anchor (1200) may cause the cam pins (1228) to travel along the cam pathways (1230) which may cause the anchoring cams (1222) to be displaced downward to disengage or detach the anchor (1200) from the body of the elongate instrument or catheter. The deployable anchor may be restored to its neutral or undeployed state. In the neutral state, the flex member (1206) may be displaced along the length inside a lumen of the elongate instrument or catheter, such as inside the operation tube. The flex member (1206) may be displaced by activating a pull wire that may be coupled to the flex member to pull the flex member (1206) toward the proximal portion of the elongate instrument or by activating push tubes or control members to displace or push the flex member toward the distal portion of the elongate instrument.

Splayer or Control Unit

FIG. 13A through FIG. 13F illustrate one variation of a control unit or splayer configured to accommodate and operate multiple flex members, wherein the control unit may include active control components for selective operation or displacement of the flex members. FIG. 13A illustrates one variation of a control unit (1300) and an elongate instrument or catheter (1302) coupled to the control unit. The control unit (1300) includes interface grooves or channels (1304) where the flex tubes (1306), pull wires (1314-1), and anchor wires (1314-2) may be disposed. The control unit (1300) may also include drive pulleys (1326) and drive pins (1328) configured to operate pull wires and anchor wires. The drive pins (1328) may be operated by one or more drive mechanisms in the instrument driver (not shown). The drive pins (1328) may drive the drive pulleys (1326) to operate the pull wires (1314-1) and anchor wires (1314-2) to respectively steer or articulate the elongate instrument (1302) as well as drive or displace the flex tubes (1306). FIG. 13B illustrates a close up exposed detail view (View 9-9) of the control unit (1300) and some of its components and features, such as the interface grooves or channels (1304) where the flex tubes (1306) are disposed within the control unit. Furthermore, the control unit (1300) may also include interface slides (1308) which may be configured to drive or displace the flex tubes (1306) as illustrated in detail view (View 10-10) of FIG. 13C. The interface slide (1308) may be operated by a drive mechanism or an interface slide carriage (1310) located in the instrument driver (1316) of a robotic system, as illustrated in FIG. 13D. The interface slide carriage (1310) may be operated by a worm gear, a screw drive, a rail system or any suitable motion control system that allows the interface slide carriage to be moved or displaced, such that the interface slide maybe displaced to act on the flex tubes (1306). FIG. 13E illustrates a further close-up detail view of the control unit (1300). This close-up detail view shows that the flex tubes (1306), pull wires (1314-1) and anchor wires (1314-2) are disposed in interface grooves or channels (1304-1), while interface grooves or channels (1304-2) may be used by the interface slides (1308) as guide tracks or guide channels for traversing up and down the length of the control unit to displace the flex tubes (1306). FIG. 13F illustrates the underside of the control unit (1300). As shown in this figure, the interface slides (1308) may be exposed through the interface grooves or channels (1304-1), such that the interface slides (1308) may be interfaced with the interface slide carriage (1310) in the instrument driver (1316).

Various Implementations of Flex Members

FIG. 14A through FIG. 14D illustrate various embodiments where flex tubes may be secured, placed, or positioned to obtain various variability of shape and/or curvature of an elongate instrument by way of active displacement of the flex tube members as previously described. In addition, the various embodiments, as illustrated in FIG. 14A through FIG. 14D may also be obtained or configured by way of fixedly coupling the distal portions of the flex tubes as provided by passively controlled or actively controlled flex tubes installations. FIG. 14A illustrates an initial state in which one or more flex tubes and their associated components of an elongate instrument (1400) may be displaced and/or secured to a first position or location (1400-1), e.g., by a deployable anchor or fixed coupling, along the length of the elongate instrument in accordance with one embodiment. In this example, the elongate instrument (1400) may have substantially two sections of variability (1402-1 and 1402-2) to steer and/or adjust the shape and/or curvature of the elongate instrument (1400). Section of variability may be described as a portion of the elongate instrument having particular characteristics of axial stiffness, flexibility, and pliability; lateral stiffness, flexibility, and pliability; bending stiffness, flexibility, and pliability, etc. FIG. 14B illustrates another embodiment in which one of a plurality of flex tubes and their associated components of an elongate instrument (1400) may be displaced and/or secured to a second position or location (1400-2) on the elongate instrument (1400), while one or more different flex tubes may be displaced and/or secured to a first position or location (1400-1) on the elongate instrument (1400). In this example, the elongate instrument (1400) may have substantially three sections of variability (1002-1, 1002-2, and 1002-3) to steer and/or adjust the shape and/or curvature of the elongate instrument (1400). FIG. 14C illustrates another embodiment in which one of a plurality of flex tubes and their associated component of an elongate instrument (1400) may be displaced and/or secured to a second position or location (1400-2) on the elongate instrument (1400), while a different flex tube may be displaced and/or secured to a third position or location (1400-3), and one or more of other flex tubes may be displaced and/or secured to a first position or location (1400-1) on the elongate instrument (1400). In this example, the elongate instrument may have substantially four sections of variability (1402-1, 1402-2, 1402-3, and 1402-4) to steer and/or adjust the shape and/or curvature of the elongate instrument (1400). FIG. 14D illustrates another embodiment in which one of a plurality of flex tubes and their associated components of an elongate instrument (1400) may be displaced and/or secured to a fourth position or location (1400-4), while another one of a plurality of flex tubes may be displaced and/or secured to a second position or location (1400-2) on elongate instrument (1400), another different flex tube may be displaced and/or secured to a third position or location (1400-3), and another flex tubes may be displaced and/or secured to a first position or location (1400-1) on the elongate instrument (1400). In this example, the elongate instrument may have substantially five sections of variability (1402-1, 1402-2, 1402-3, 1402-4, and 1402-5) to steer and/or adjust the shape and/or curvature of the elongate instrument (1400). As described, the various embodiments illustrated in this example may be obtained by displacing the flex tubes through the application of displaceable control of the flex tubes or by fixedly coupling the distal portion of the flex tubes at the various locations along the length of the elongate instrument in actively control configurations or passively controlled configurations.

FIG. 15A through 15C illustrate a simplified construction of an elongate instrument (1500) with variable shape control and support in accordance with one embodiment. In this embodiment, the elongate instrument may be formed into a desired shape in a passive manner. That is instead of using pull wires to steer the elongate instrument (1500) into a desired shape or curvature, a separate shape or curvature forming instrument (1550) may be used to put the elongate instrument (1500) into a desired shape or curvature. The shape or curvature forming instrument (1550) may be a miniaturized instrument that when it is in its neutral state, it may be substantially flexible, pliable, and may conform to any shape or curvatures without significant resistance. As illustrated in FIG. 11A, the shape forming instrument (1550) in its neutral state may conform to the shape of the elongate instrument (1500). However, when it is activated, it may become erected or stiffened into a preprogrammed or predetermined shape or curvature, as illustrated in FIG. 15B. The elongate instrument (1500) in its neutral state conforms to the shape or curvature of the shape forming instrument (1550). Once the desired shape or curvature is formed, flex tubes (1506-1 and 1506-2) may be locked in place to lock the elongate instrument (1500) into the desired shape or curvature, as illustrated in FIG. 15B. The shape forming instrument (1550) may then be deactivated, so that it may become substantially flexible and pliable again. In its deactivated or neutral state, the shape forming instrument (1550) may then be withdrawn from the elongate instrument (1500), as indicated by the arrow in FIG. 15C. As such, the flexible and steerable elongate instrument (1500) with variable shape control and support may be comprised of a simplified construction with one or more flex tubes and active control to lock the flex tube after the elongate instrument (1500) has acquired a desired shape or curvature. For illustrative purposes, this example describes a method of using two flex tubes to lock or maintain an elongate instrument in a particular desired shape or curvature. As may be appreciated, one or more flex tubes may be used to lock or maintain an elongate instrument in a particular desired shape or curvature. In addition, the flex tubes may be positioned or disposed in various locations, positions, or orientations within the wall or lumens of the elongate instrument to allow the flex tubes to lock or maintain the elongate instrument in various shapes, curvatures, or orientations.

FIG. 16A through FIG. 16J illustrate various embodiments where flex tubes and associated components may be disposed within the wall or lumens of an elongate instrument to provide various variety of steering, articulation, shape, and curvature control to the elongate instrument. The flex tubes may be secured, placed, or positioned in the elongate instrument to obtain various variety or variability of steering, articulation, shape and/or curvature control of an elongate instrument by way of active displacement of the flex tube members as previously described in this disclosure. In addition, the various embodiments, as illustrated in FIG. 16A through FIG. 16J, may also be obtained or configured by way of fixedly coupling the distal portions of the flex tubes as described in this disclosure by way of passive control or active control configurations or installations of flex tubes and associated components. As illustrated in FIG. 16A through 16J, an elongate instrument or catheter (1600) may include an elongate body with a working lumen (1618) and one or more control lumens (1604) where control elements, such as flex tubes (1606), control wires (1614), and various associated components may be disposed. The embodiments as illustrated in FIG. 16A through 16J are for illustrative purposes only and not to limit the variety of possible configurations in which the flex tubes and associated components may be implemented to provide various means to steer and articulate the elongate instrument or to control the shape or curvature of the body of the elongate instrument. With that understanding, FIG. 16A through 16F illustrate a sample of variations in which one set of flex tubes (1606) may be configured or implemented in a set of control lumens (1604) within the body of an elongate instrument (1600). For example, the distal portion of the flex tubes (1606) and associated pull wires (1614) may be attached, coupled, or secured to any portion or location on the body of the elongate instrument (1600) to affect the stiffness and steering, articulation, and bending characteristics of the elongate instrument. For the configuration with active control of the flex tubes (1606), the implementation may also include push tubes or control members (1608) to displace the proximal portion of the flex tubes. FIG. 16G through FIG. 16J illustrate a sample of variations in which a plurality of flex tubes (1606) may be disposed or implemented in a control lumen (1604) of an elongate instrument (1600) to create various stiffness, and steering, articulation, and bending characteristics of the elongate instrument. FIG. 16G and FIG. 16H illustrate examples of a plurality of flex tubes (1606) configured in a substantially parallel configuration within a control lumen (1604) affect the stiffness and steering, articulation, and bending characteristics of the elongate instrument. The flex tubes (1606) may be configured or implemented by way of passively controlled, actively controlled, displaceable controlled configuration, or combination of passively controlled, actively controlled or displaceable controlled configuration. FIG. 16I and FIG. 16J illustrate a sample of variations in which one of the plurality of flex tubes (e.g., 1606-1) in a control lumen (1604) may be configured in a passively controlled manner, while one or more other flex tubes (160602) may be configured in a passively controlled manner, actively controlled manner, or displaceable controlled manner.

Various Methods of Application

FIG. 17A through FIG. 17F illustrate various methods in which an elongate instrument with passive control, active control, or displaceable control may be used to approach and treat a target site or tissue structure in a minimally invasive procedure. In one method as FIG. 17A illustrates, at least a portion, e.g., a first portion or distal portion, of an elongate instrument may be inserted into a patient percutaneously through the skin either by way of an incision or orifice, as described in Step 1702. Advance at least a portion, e.g., first portion or distal portion, of the elongate instrument through a pathway inside the patient, as described in Step 1704. At least a portion, e.g., a second portion or proximal portion, of the elongate instrument may be manipulated to conform, adopt, or match a shape or curvature of the pathway as the elongate instrument is being advanced through the pathway, as described in Step 1706. Steer, or articulate at least a portion, e.g., first portion or distal portion, of the elongate instrument around other curvatures of the pathway as the elongate instrument is navigated through the anatomy of the patient, as described in Step 1708. In another method as FIG. 17B illustrates, at least a portion, e.g., a first portion or distal portion, of an elongate instrument may be inserted into a patient percutaneously through the skin either by way of an incision or orifice, as described in Step 1712. Advance at least a portion, e.g., first portion or distal portion, of the elongate instrument through a pathway inside the patient, as described in Step 1714. At least a portion, e.g., a second portion or proximal portion, of the elongate instrument may be manipulated to conform, adopt, or match a shape or curvature of the pathway as the elongate instrument is being advanced through the pathway, as described in Step 1716. At least a portion, e.g., first portion or distal portion, of the elongate instrument may be steered or articulated around other curvatures of the pathway as the elongate instrument is navigated through the anatomy of the patient, as described in Step 1718. In addition, articulation forces from steering the one portion, e.g., first portion or distal portion, of the elongate instrument may be decoupled from another portion, e.g., second portion or proximal portion, of the elongate instrument, as described in Step 1719. Furthermore, the conformed, adopted, or matched shape or curvature of the one portion, e.g., second portion or proximal portion, may be maintained by way of decoupling the one portion, e.g., first portion or distal portion, of the elongate instrument from another portion, e.g., second portion or proximal portion, of the elongate instrument. The act of decoupling the articulation or steering forces may include preventing a flex member from moving in reaction to the articulation or steering forces and compressing the flex member to support the articulating or steering forces. In another method as FIG. 17C illustrates, at least a portion, e.g., a first portion or distal portion, of an elongate instrument may be inserted into a patient percutaneously through the skin either by way of an incision or orifice, as described in Step 1722. Advance at least a portion, e.g., first portion or distal portion, of the elongate instrument through a pathway inside the patient, as described in Step 1723. At least a portion, e.g., a second portion or proximal portion, of the elongate instrument may be manipulated to conform, adopt, or match a shape or curvature of the pathway as the elongate instrument is being advanced through the pathway, as described in Step 1724. At least a portion, e.g., first portion or distal portion, of the elongate instrument may be steered or articulated around other curvatures of the pathway as the elongate instrument is navigated through the anatomy of the patient, as described in Step 1725. In addition, a control member may be advanced a control unit or splayer against a flex member or flex tube, as described in Step 1726, at the proximal portion of the flex member to hold the flex member at a particular position or orientation. As such, at least a portion, e.g., second portion or proximal portion, of the elongate instrument may be locked in the conformed, adopted or matched shape or curvature. In another method as FIG. 17D illustrates, an elongate instrument may be inserted into a patient percutaneously through the skin either by way of an incision or orifice, as shown in Step 1732. The elongate instrument may include a first portion, a second portion, and a third portion, or a distal portion, a mid portion, and a proximal portion. The first portion or distal portion and the second portion or mid portion of the elongate instrument may be advanced through a pathway inside the patient, as described in Step 1734. At least a portion, e.g., second portion or mid portion, of the elongate instrument may be manipulated to conform, adopt, or match a shape or curvatures of the pathway as the elongate instrument is being advanced through the pathway, as described in Step 1736. The second portion or mid portion of the elongate instrument may be locked in place to maintain the conformed, adopted, or matched shape or curvatures of the pathway while the first portion or distal portion of the elongate instrument may be manipulated to assume a curvature independent of the second portion or mid portion, as described in Step 1738. In another method as FIG. 17E illustrates, an elongate instrument may be inserted into a patient percutaneously through the skin either by way of an incision or orifice, as shown in Step 1742. The elongate instrument may include a first portion, a second portion, and a third portion, or a distal portion, a mid portion, and a proximal portion. The first portion or distal portion and the second portion or mid portion of the elongate instrument may be advanced through a pathway inside the patient, as described in Step 1743. At least a portion, e.g., second portion or mid portion, of the elongate instrument may be manipulated to conform, adopt, or match a shape or curvatures of the pathway as the elongate instrument is being advanced through the pathway, as described in Step 1744. Controlling the displacement of a flex member within the elongate instrument, wherein the flex member may be configured to assist with steering or articulation of the elongate instrument, as described in Step 1746. Steering a first portion or a second portion of the elongate instrument around curvatures of the pathway inside the patient, as described in Step 1748. In another method as FIG. 17F illustrates, an elongate instrument may be inserted into a patient percutaneously through the skin either by way of an incision or orifice, as shown in Step 1752. The elongate instrument may include a first portion, a second portion, and a third portion, or a distal portion, a mid portion, and a proximal portion. The first portion or distal portion and the second portion or mid portion of the elongate instrument may be advanced through a pathway inside the patient, as described in Step 1753. At least a portion, e.g., second portion or mid portion, of the elongate instrument may be manipulated to conform, adopt, or match a shape or curvatures of the pathway as the elongate instrument is being advanced through the pathway, as described in Step 1754. Controlling the displacement of a flex member along a length of the elongate instrument, wherein the flex member may be disposed within the elongate instrument and the flex member may be configured to assist with steering or articulation of the elongate instrument, as described in Step 1755. The stiffness of at least a portion, e.g., first portion or distal portion, of the elongate instrument may be altered by the displacement of the flex member, as described in Step 1756. In addition, the radius of curvature for a least a portion of the elongate instrument may be changed by the displacement of the flex member, as described in Step 1757. After altering the stiffness and/or radius of curvature of at least a portion of the elongate instrument, steer a portion, e.g., first portion or second portion, of the elongate instrument around curvatures of the pathway inside the patient, as described in Step 1758.

Multiple embodiments and variations of the various aspects of the invention have been disclosed and described herein. Many combinations and permutations of the disclosed system may be useful in minimally invasive medical intervention and diagnostic procedures, and the system may be configured to support various flexible robotic instruments. One of ordinary skill in the art having the benefit of this disclosure would appreciate that the foregoing illustrated and described embodiments of the invention may be modified or altered, and it should be understood that the invention generally, as well as the specific embodiments described herein, are not limited to the particular forms or methods disclosed, but also cover all modifications, equivalents and alternatives. Further, the various features and aspects of the illustrated embodiments may be incorporated into other embodiments, even if not so described herein, as will be apparent to those ordinary skilled in the art having the benefit of this disclosure.

Although particular embodiments of the present invention have been shown and described, it should be understood that the above discussion is not intended to limit the present invention to these embodiments. It will be obvious to those skilled in the art that various changes and modifications may be made without departing from the spirit and scope of the present invention. Thus, the present invention is intended to cover alternatives, modifications, and equivalents that may fall within the spirit and scope of the present invention as defined by the claims. 

What is claimed is:
 1. A steerable elongate instrument, comprising: an elongate body comprising a proximal portion, a distal portion, a first lumen and a plurality of secondary lumens within the elongate body; a plurality of flex members disposed within the secondary lumens, wherein each flex member is disposed within a different one of the secondary lumens, wherein a distal end of each of the flex members is anchored to the distal portion of the elongate body and a proximal portion of each of the flex members is fixedly coupled to a control unit positioned proximal to the elongate body, and wherein each flex member comprises a buffer length extending proximally beyond the respective secondary lumen and forming a service loop, each service loop adjustable such that, when a portion of the elongate body bends, the service loop positioned along a stretched region of the elongate body slides at least partially into the respective secondary lumen and the service loop positioned along a contracted region of the elongate body slides at least partially out of the respective secondary lumen; and a plurality of pull wires disposed within the flex members, wherein each pull wire is disposed within a different one of the flex members, and wherein a distal portion of each pull wire is coupled to the distal portion of the elongate body and a proximal portion of each pull wire is operatively coupled to a gear or pulley of the control unit.
 2. The elongate instrument of claim 1, wherein the distal portion of each pull wire is coupled to the elongate body through a control ring fixedly coupled to the elongate body.
 3. The elongate instrument of claim 1, further comprising a plurality of liners, wherein a respective liner is disposed within each of the secondary lumens.
 4. The elongate instrument of claim 3, wherein the respective liner is disposed between the secondary lumen and the flex member.
 5. The elongate instrument of claim 1, further comprising a plurality of support members, each support member comprising: a distal portion fixedly coupled to the distal portion of the elongate body; and a proximal portion operatively coupled to the distal end of one of the flex members.
 6. The elongate instrument of claim 5, wherein the proximal portion of each support member slidably engages the distal end of the respective flex member.
 7. The elongate instrument of claim 6, wherein each support member engages the respective flex member through a lumen of the respective flex member.
 8. The elongate instrument of claim 1, wherein each of the flex members is a coil tube.
 9. The elongate instrument of claim 1, wherein each of the flex members is a ring tube.
 10. The elongate instrument of claim 1, further comprising a plurality of operation tubes.
 11. A steerable elongate instrument, comprising: an elongate body comprising a proximal portion, a distal portion, a first lumen and at least two secondary lumens within the elongate body; at least two flex members disposed within the at least two secondary lumens, wherein each flex member is disposed within a different one of the secondary lumens, wherein the at least two flex members are configured to provide steering control to a first portion of the elongate body and load bearing support to a second portion of the elongate body, wherein each of the at least two flex members includes a buffer length configured such that at least a portion of the buffer length forms a service loop that is slideable into and out of the elongate body at a proximal end of the elongate body, wherein a distal end of each flex member is anchored to the distal portion of the elongate body, wherein a proximal portion of each flex member is fixedly coupled to a control unit positioned proximal to the elongate body, and wherein, when a portion of the elongate body bends, a first one of the at least two flex members located on an extended region of the elongate body slides at least partially into one of the at least two secondary lumens, and a second one of the at least two flex members located on a contracted region of the elongate body slides at least partially out of into another of the at least two secondary lumens; and at least two pull wires, wherein each pull wire is disposed within one of the at least two flex members, wherein a distal portion of each pull wire is coupled to the distal portion of the elongate body, and a proximal portion of each pull wire is operatively coupled to the control unit.
 12. The elongate instrument of claim 11, wherein the at least two flex members anchored to the distal portion of the elongate body are configured to decouple articulation or steering forces of the first portion of the elongate body away from the second portion of the elongate body to the at least two flex members, thereby preventing compression of the second portion of the elongate body from the articulation or steering forces while maintaining flexibility of the second portion of the elongate body.
 13. The elongate instrument of claim 11, further comprising at least two liners disposed within the at least two secondary lumens, wherein each of the at least two liners is disposed within one of the at least two secondary lumens, and wherein each of the at least two liners comprises a slidable surface for the at least two flex members to slide within the secondary lumens.
 14. The elongate instrument of claim 13, wherein the slidable surface of each of the liners decouples each of the flex members from the elongate body.
 15. The elongate instrument of claim 11, wherein the at least two pull wires are coupled to the elongate body through a control ring fixedly coupled to the elongate body.
 16. The elongate instrument of claim 11, further comprising a support member, comprising: a distal portion fixedly coupled to the distal portion of the elongate body; and a proximal portion operatively coupled to the distal ends of the at least two flex members.
 17. The elongate instrument of claim 16, wherein the proximal portion of the support member is configured to slide along the distal ends of the at least two flex members.
 18. The elongate instrument of claim 17, wherein the proximal portion of the support member slides along inside a lumen of each of the at least two flex members.
 19. The instrument of claim 11, wherein the at least two flex members are configured to selectively decouple articulation or steering forces of the first portion of the elongate body away from the second portion of the elongate body, thereby preventing compression of the second portion of the elongate body while maintaining flexibility of the second portion of the elongate body.
 20. A steerable elongate instrument, comprising: an elongate body comprising a proximal portion, a distal portion, a primary lumen and a plurality of secondary lumens within the elongate body; a plurality of flex members disposed within the plurality of secondary lumens, wherein each flex member is disposed within a different one of the secondary lumens, the flex members configured to provide steering control to a distal portion of the elongate body and load bearing support to a proximal portion of the elongate body, wherein each of the flex members includes a buffer length configured such that at least a portion of the buffer length forms a service loop that is slideable into and out of the elongate body at a proximal end of the elongate body, wherein a distal end of each flex member is anchored to the distal portion of the elongate body, wherein a proximal portion of each flex member is fixedly coupled to a control unit positioned proximal to the elongate body, and wherein, when a portion of the elongate body bends, the service loop positioned along a stretched region of the elongate body slides at least partially into the respective secondary lumen and the service loop positioned along a contracted region of the elongate body slides at least partially out of the respective secondary lumen; and a plurality of pull wires disposed within the plurality of flex members, wherein each pull wire is disposed within a different one of the flex members, and wherein a distal portion of each pull wire is coupled to the distal portion of the elongate body at a different location and a proximal portion of each pull wire is operatively coupled to the control unit, the control unit being configured to operate the pull wires for applying forces to articulate or steer the distal portion of the elongate body. 